1. Field of the Invention
The present invention relates generally to a water system operators end-to-end control of water quality in a water filtration, purification and distribution system all the way to a consumer's point-of-use, and more specifically to a system, method, and apparatus to achieve end-to-end water quality through the controlled distribution of water filtration and purification products.
2. Problems in the Art
The Safe Drinking Water Act (SDWA) was originally passed by Congress in 1974 to protect public health by regulating the nation's public drinking water supply. The law was amended in 1986 and 1996 and requires many actions to protect drinking water and its sources, including rivers, lakes, reservoirs, springs, and ground water wells. The SDWA does not regulate private wells which serve fewer than 25 individuals. The SDWA authorizes the United States Environmental Protection Agency (US EPA) to set national health-based standards for drinking water to protect against both naturally-occurring and man-made contaminants that may be found in drinking water. The US EPA, states, and public and private water systems then work together to make sure that these standards are met.
Millions of Americans receive high quality drinking water every day from their public water systems, (which may be publicly or privately owned). Nonetheless, drinking water safety cannot be taken for granted. There are a number of threats to drinking water: improper disposal of chemicals, animal wastes, pesticides, human wastes, wastes injected deep underground, and naturally-occurring substances can all contaminate drinking water. Likewise, drinking water that is not properly treated or disinfected, or which travels through an improperly maintained distribution system, may also pose a health risk.
Originally, the SDWA focused primarily on treatment as the means of providing safe drinking water at the tap. The 1996 amendments greatly enhanced the existing law by recognizing source water protection, operator training, funding for water system improvements, and public information as important components of safe drinking water. This approach ensures the quality of drinking water by protecting it from source to tap.
The SDWA applies to every public water system in the United States. There are currently more than 160,000 public water systems providing water to almost all Americans at some time in their lives. The responsibility for making sure these public water systems provide safe drinking water is divided among US EPA, states, tribes, water systems, and the public. The SDWA provides a framework in which these parties work together to protect this valuable resource. Regardless of various Government Agencies and the public water system policies they establish and enforce for the good of the public, public water can often be sub-standard and questionable in quality, what is needed is an end-to-end control of water system quality by a water system operators from their plants, through their aging distribution systems, across the water meter demarcation to the consumer's point-of-use, such as, but not limited to, a tap, faucet, hydrant, spigot, spout, valve, bib, etc.
The US EPA sets national standards for drinking water based on sound science to protect against health risks, considering available technology and costs. These National Primary Drinking Water Regulations set enforceable maximum contaminant levels for particular contaminants in drinking water or required ways to treat water to remove contaminants. Each standard also includes requirements for water systems to test for contaminants in the water to make sure standards are achieved. In addition to setting these standards, the US EPA provides guidance, assistance, and public information about drinking water, collects drinking water data, and oversees state drinking water programs.
The most direct oversight of water systems is conducted by state drinking water programs. States can apply to the US EPA for “primacy,” the authority to implement SDWA within their jurisdictions, if they can show that they will adopt standards at least as stringent as the US EPA's and make sure water systems meet these standards. All states and territories, except Wyoming and the District of Columbia, have received primacy. While no native American tribe has yet applied for and received primacy, four tribes currently receive “treatment as a state” status, and are eligible for primacy. States, or the US EPA acting as a primacy agent, make sure water systems test for contaminants, review plans for water system improvements, conduct on-site inspections and sanitary surveys, provide training and technical assistance, and take action against water systems not meeting standards.
To ensure that drinking water is safe, the SDWA sets up multiple barriers against pollution. These barriers include: source water protection, treatment, distribution system integrity, and public information. Public water systems are responsible for ensuring that contaminants in tap water do not exceed the standards. Water systems treat the water, and must test their water frequently for specified contaminants and report the results to states. If a water system is not meeting these standards, it is the water supplier's responsibility to notify its customers. Many water suppliers are also now required to prepare annual reports for their customers. The public is responsible for helping local water suppliers to set priorities, make decisions on funding and system improvements, and establish programs to protect drinking water sources. Water systems across the nation rely on citizen advisory committees, rate boards, volunteers, and civic leaders to actively protect this resource in every community in America. Regardless of various Government Agencies and the public water system policies they establish and enforce for the good of the public, public water can often be sub-standard and questionable in quality, what is needed is an end-to-end control of water system quality by a water system operators from their plants, through their aging distribution systems, across the water meter demarcation to the consumer's point-of-use, such as, but not limited to, a tap, faucet, hydrant, spigot, spout, valve, bib, etc.
Essential components of safe drinking water include protection and prevention. States and water suppliers must conduct assessments of water sources to see where they may be vulnerable to contamination. Water systems may also voluntarily adopt programs to protect their watershed or wellheads, and states can use legal authorities from other laws to prevent pollution. The SDWA mandates that states have programs to certify water system operators and make sure that new water systems have the technical, financial, and managerial capacity to provide safe drinking water. The SDWA also sets a framework for the Underground Injection Control (UIC) program to control the injection of wastes into ground water. The US EPA and states implement the UIC program, which sets standards for safe waste injection practices and bans certain types of injection altogether. All of these programs help prevent the contamination of drinking water.
The US EPA sets national standards for tap water which help ensure consistent quality in our nation's water supply. Regardless of various Government Agencies and the public water system policies they establish and enforce for the good of the public, public water can often be sub-standard and questionable in quality, what is needed is an end-to-end control of water system quality by a water system operators from their plants, through their aging distribution systems, across the water meter demarcation to the consumer's point-of-use, such as, but not limited to, a tap, faucet, hydrant, spigot, spout, valve, bib, etc.
The US EPA prioritizes contaminants for potential regulation based on risk and how often they occur in water supplies. To aid in this effort, certain water systems monitor for the presence of contaminants for which no national standards currently exist and collect information on their occurrence. The US EPA sets a health goal based on risk (including risks to the most sensitive people, e.g., infants, children, pregnant women, the elderly, and the immuno-compromised). The US EPA then sets a legal limit for the contaminant in drinking water or a required treatment technique, and also performs a cost-benefit analysis and obtains input from interested parties when setting standards. The US EPA is currently evaluating the risks from several specific health concerns, including: microbial contaminants (e.g., Cryptosprodium and Giardia) the byproducts of drinking water disinfection (radon, arsenic), and water systems that don't currently disinfect their water, but get it from a potentially vulnerable ground water source.
The US EPA provides grants to implement state drinking water programs, and to help each state set up a special fund to assist public water systems in financing the costs of improvements (called the drinking water state revolving fund). Small water systems are given special consideration, since small systems may have a more difficult time paying for system improvements due to their smaller customer base. Accordingly, the US EPA and states provide them with extra assistance (including training and funding) as well as allowing, on a case-by-case basis, alternate water treatments that are less expensive, but still protective of public health.
National drinking water standards are legally enforceable, which means that both the US EPA and states can take enforcement actions against water systems not meeting safety standards. The US EPA and states may issue administrative orders, take legal actions, or fine utilities. The US EPA and states also work to increase the understanding of, and compliance with, standards. The US EPA should strongly consider mandating compliance all the way to the consumer's point-of-use for the good of the public they serve. In addition to an increase in public health, the anti-terrorism benefits are myriad.
The SDWA recognizes that since everyone drinks water, everyone has the right to know what's in it and where it comes from. All water suppliers must notify consumers quickly when there is a serious problem with water quality. Water systems serving the same people year-round must provide annual consumer confidence reports on the source and quality of their tap water. States and the US EPA must prepare annual summary reports of water system compliance with drinking water safety standards and make these reports available to the public. The public must have a chance to be involved in developing source water assessment programs, state plans to use drinking water state revolving loan funds, state capacity development plans, and state operator certification programs.
The Government Performance and Results Act (GRPA) requires government agencies to develop plans for what they intend to accomplish, measure how well they are doing, make appropriate decisions based on the information they have gathered, and communicate information about their performance to Congress and to the public.
The US EPA strategic targets for community water systems in the United States are: 80% of community water systems and 95% of the population served by them are to provide drinking water that meets all existing health-based standards with a compliance date of no later than January 2008.
In order to monitor compliance with these targets, Community Water Systems will be measured on the following health-based violations, which include 1) Maximum Contaminant Level (MCL), 2) Maximum Residual Disinfectant Level (MRDL), and 3) Treatment Technique (TT) violations.
A typical water treatment plant uses the following six step process to process raw water into drinking water. Incoming raw ground or surface water is 1) chlorinated, 2) coagulation, 3) flocculation, 4) sedimentation, 5) chlorination, 6) filtration and release of the finished drinking water into the distribution system. However, water that is not adequately filtered and purified can contain inorganic pollutants such as lead, herbicides, pesticides, insecticides, the gasoline additive MTBE (Methyl Tertiary-Butyl Ether), volatile organic compounds (VOCs), and disinfection byproducts.
In addition, water that is not adequately filtered and purified can contain microbial contaminants that are by far a greater threat that inorganic pollutants. The first is protozoa. Protozoa include the well-known Giardia, and the not-so-well-known Cryptosporidium. These two protozoa have been detected in 90% of U.S. surface water. Protozoa are the largest organisms of the three categories, ranging in size from 1-16 microns. They are more resistant to disinfection by iodine or chlorine than either bacteria or virus, but can be effectively filtered. Giardia is relatively large and easy to catch, but Cryptosporidium is more likely to pass through units which depend upon filtration for parasite removal. The second category is bacteria. Bacteria include such commonly-known organisms as Campylobacter, E. coli, Vibrio cholera, and Salmonella. Bacteria are intermediate-sized organisms, ranging from 0.2 to about 10 microns. The third category is viruses. Commonly known viruses include Rotavirus, Hepatitis A, Norwalk, and Polio. Viruses are truly tiny; they range in size between 0.02 and 0.085 microns, which makes them extremely difficult to filter. Viruses respond well to disinfection, and can be effectively inactivated using a purifier proven to remove or inactivate 99.99% of virus.
In addition, public drinking water may have an objectionable turbidity, contain hydrogen sulfide, may be too acidic or alkaline, or may contain radon or radium.
Water treatment plants may also replace the chlorination of incoming raw water with an ozone process. Intermediate filters, and biological filters may be added to the process, but 98% of the water treatment plants in the United States chlorinate the processed drinking water that is released in the distribution system. There exists a tension between the positive benefits of chlorinating water and the increasing amount of research related to the negative effects of chlorinating water.
Chlorine has been linked to several different kinds of cancer, learning disorders in children, heart trouble, premature senility, hypertension in adult males, and birth defects.
On the other hand, chlorination has played a critical role in protecting the United States' drinking water supply from waterborne infectious diseases for 90 years. The filtration, purification, and disinfection of drinking water have been responsible for a large part of the 50 percent increase in life expectancy in this century. The filtration and purification by chlorination of drinking water is undoubtedly the most significant public health advance of the past 1,000 years. However, water that is not adequately filtered and purified can contain inorganic pollutants such as lead, herbicides, pesticides, insecticides, the gasoline additive MTBE (Methyl Tertiary-Butyl Ether), volatile organic compounds (VOCs), and disinfection byproducts.
In addition, water that is not adequately filtered and purified can contain microbial contaminants that are by far a greater threat that inorganic pollutants. The first is protozoa. Protozoa include the well-known Giardia, and the not-so-well-known Cryptosporidium. These two protozoa have been detected in 90% of U.S. surface water. Protozoa are the largest organisms of the three categories, ranging in size from 1-16 microns. They are more resistant to disinfection by iodine or chlorine than either bacteria or virus, but can be effectively filtered. Giardia is relatively large and easy to catch, but Cryptosporidium is more likely to pass through units which depend upon filtration for parasite removal. The second category is bacteria. Bacteria include such commonly-known organisms as Campylobacter, E. coli, Vibrio cholera, and Salmonella. Bacteria are intermediate-sized organisms, ranging from 0.2 to about 10 microns. The third category is viruses. Commonly known viruses include Rotavirus, Hepatitis A, Norwalk, and Polio. Viruses are truly tiny; they range in size between 0.02 and 0.085 microns, which makes them extremely difficult to filter. Viruses respond well to disinfection, and can be effectively inactivated using a purifier proven to remove or inactivate 99.99% of virus.
In addition, public drinking water may have an objectionable turbidity, contain hydrogen sulfide, may be too acidic or alkaline, or may contain radon or radium.
Chlorinated drinking water's chief benefit is the protection of public health through the control of waterborne diseases. It plays a paramount role in controlling pathogens in water that cause human illness, as evidenced by the virtual absence of waterborne diseases such as typhoid and cholera in developed countries.
Untreated or inadequately treated drinking water supplies remain the greatest threat to public health, especially in developing countries, where nearly half the population drinks contaminated water. In these countries, diseases such as cholera, typhoid and chronic dysentery are endemic and kill young and old alike. In 1990, over three million children under the age of five died of diarrheal diseases. Unfortunately, the availability of safe drinking water in many areas is practically nonexistent, due to poverty, poor understanding of water contamination, and lack of a treatment and delivery infrastructure.
International assistance groups, including the World Health Organization and the Pan American Health Organization (PAHO), have long-standing technical assistance and education programs to improve water supply and sanitation practices. It has been estimated that such improvements—including chlorine disinfection—can prevent 25 percent of all diarrheal outbreaks and reduce childhood mortality by equal levels.
An example of the continuing public health threat from waterborne disease outbreaks occurred in Peru in 1991, where a major causative factor was the absence or inadequacy of drinking water disinfection. This failure to disinfect was partly based on concern about U.S. reports on disinfection by-products. The result: a five-year epidemic of cholera, its first appearance in the Americas in this century. The epidemic spread to 19 Latin American countries and has been only partially abated through public health interventions supported by PAHO's advice and technical assistance. Nearly a million cases and 10,000 deaths have been reported.
These statistics strongly reinforce the concept that water disinfection must be a primary tool in protecting public health worldwide. As noted by the American Academy of Microbiology, “The single, most important requirement that must be emphasized is that disinfection of a public water supply should not be compromised.”
At the 1992 First International Conference on the Safety of Water Disinfection, several researchers described the costs associated with microbiological disease as well as the benefits of illness avoided through water treatment. Real health care savings can be realized from preventing and eliminating microbial contamination in drinking water supplies.
In his conference presentation, Dr. Pierre Payment of the University of Quebec stated that the “social cost of ‘mild’ gastrointestinal illness in industrialized countries is several orders of magnitude higher than costs associated with acute hospitalized cases.” For example, in the United States, annual costs were estimated to be $9.5 billion (1985 dollars) for cases with no consultation with a physician, $2.7 billion for those with consultations, and only $760 million for those requiring hospitalization.
Dr. Payment presented data estimating that in 1985; about 500,000 hospitalizations and 3,000 deaths were due to gastrointestinal illnesses in the United States, the majority being of unknown origin. His study assumed that these numbers are grossly underestimated due to unreported or unidentified illnesses. Over 13 percent were due to viral illnesses, 4.9 percent were bacterial and 1.1 percent was parasitic. About 80 percent were presumed noninfectious. One out of ten deaths from gastroenteritis could be due to viruses. Commenting on Dr. Payment's report, the American Academy of Microbiology noted, “A decrease in morbidity and mortality is not the only benefit which should be considered in a cost-benefit analysis . . . The benefits of microbiologically safe water go beyond the absence of disease, and affect the productivity of industry, as well as the prices of goods and services.”
At the same conference, a paper by Gunther F. Craun et al. discussed the cost-effectiveness of water treatment for pathogen removal. An evaluation of five pathogens and treatment costs shows the favorable economic benefits of preventing infectious waterborne diseases. The report concluded that “municipal water systems designed to prevent waterborne infectious disease are one of the most effective investments of public funds that society can make. Even conservative estimates under worst-case conditions show benefit-cost ratios of 3:1 for small systems and 8:1 for large systems. Pathogen-free drinking water is a bargain.” Regarding comparison of these benefits with potential cancer risks associated with drinking water disinfection, the group noted that the costs of preventing the relatively small carcinogenic risks may not be warranted in light of many other public health risks that should be reduced. Regardless of various Government Agencies and the public water system policies they establish and enforce for the good of the public, public water can often be sub-standard and questionable in quality, what is needed is an end-to-end control of water system quality by a water system operators from their plants, through their aging distribution systems, across the water meter demarcation to the consumer's point-of-use, such as, but not limited to, a tap, faucet, hydrant, spigot, spout, valve, bib, etc.
The addition of chlorine to our drinking water started in the late 1890's and had wide acceptance in the United States by 1920. Joseph Price, M. D, wrote a fascinating yet largely ignored book in the late 1960's, entitled Coronaries Cholesterol. Chlorine, Dr Price believes, is the primary and essential cause of atherosclerosis is chlorine. “Nothing can negate the incontrovertible fact the basic cause of atherosclerosis and resulting entities, such as heart attacks and most common forms of stokes is chlorine. The chlorine contained in processed drinking water.”
This conclusion is based on experiments using chlorine in the drinking water of chickens. The results: 95% of the chickens given chlorine added to distilled water developed atherosclerosis within a few months.
Atherosclerosis, heart attacks and the resulting problems of hardening of the arteries and plaque formation is really the last step in a series of biochemical malfunctions. Price points out it takes ten to twenty years before symptoms in humans become evident. In many ways, this is reminiscent of cancer which can take twenty to thirty years to develop.
Can chlorine be linked to cancer too? In the chlorination process itself, chlorine combines with natural organic matter decaying vegetation to form potent cancer causing trihalomethanes (THM's) or haloforms. Trihalomethanes collectively include such carcinogens as chloroforms, bromoforms carbon tectachloride, bischlorothane and others. The amount of THM's in our drinking water is theoretically regulated by the EPA. Although the maximum amount allowed by law is 100 ppb, a 1976 study showed 31 of 112 municipal water systems exceeded this limit.
According to some studies by 1975, the number of chemical contaminants found in finished drinking water exceeded 300 ppb. In 1984 over 700 chemicals had been found in our drinking water. The EPA has targeted 129 of these chemicals as posing the greatest threat to our health. Currently the EPA enforces federal standards for 34 drinking water contaminants. In July, 1990 they proposed adding 23 new ones and expects this list to grow to 85 in 1992.
Another report claims the picture is much worse. According to Troubled Waters on Tap “over 2100 contaminants have been detected in U. S. drinking water since 1974 with 190 known or suspected to cause adverse health effects at certain concentration levels. In total, 97 carcinogens and suspected carcinogens, 82 mutagens and suspected mutagens, 28 acute and chronic toxic contaminants, and 23 tumor promoters have been detected in U. S. drinking water since 1974.
Compounds in this concentration could pose serious toxic effects, either alone or in combination with other chemicals found in drinking water. Overall, available scientific evidence continues to substantiate the link between consumption of toxins in drinking water and serious public health concerns, Studies have strengthened the association between ingestion of toxins and elevated cancer mortality risks. Studies in New Orleans, La.; Eric County, N.Y., Washington County Md., and Ohio County, Ohio reveal high levels of haloforms or THM's in drinking water which results in higher levels of cancer.
The continued use of chlorine as the main drinking water disinfectant in the United States only adds to the organic chemical contamination of drinking water supplies. The current federal standard regulation of trihalomethanes do not adequately protect water consumers from the multitude of other organic chlorination by-products that have been shown in many studies to be mutagenic and toxic'
“Chlorine is so dangerous” according to biologist/chemist Dr. Herbert Schwartz,” that it should be banned. Putting chlorine in the water is like starting a time bomb. Cancer, heart trouble, premature senility, both mental and physical are conditions attributable to chlorine treated water supplies. It is making us grow old before our time by producing symptoms of aging such as hardening of the arteries. I believe if chlorine were now proposed for the first time to be used in drinking water it would be banned by the Food and Drug Administration.”
The disinfection byproducts debate has led some people to think that chlorine's use in drinking water treatment will diminish. This is highly unlikely. Other disinfectants also produce byproducts. Furthermore, chlorine is the disinfectant of choice for drinking water for a number of reasons. Its wide range of benefits can not be provided by any other single disinfectant. Chlorine-based disinfectants are the only disinfectants that provide a residual in the distribution system. This residual is an important part of the multi-barrier approach to preventing waterborne disease. The increasing need to disinfect groundwater systems may actually increase the use of chlorine for drinking water disinfection.
According to the World Health Organization, disinfection by chlorine is still the best guarantee of microbiologically safe water and is unlikely to change in the near future.
Many municipalities are experimenting with a variety of disinfectants to either take the place of chlorine or to be used in addition, as a way of cutting down on the amount of chlorine added to the water. However, these alternatives such as chlorine dioxide, bromine chloride, chloromines, etc., are just as dangerous as chlorine. We're replacing one toxic chemical with another.
There are other more appropriate ways to reduce disinfection byproducts such as precursor removal technologies that will not produce new disinfection byproducts. On the positive side, some cities are starting to use aeration carbon filtration, ultraviolet light and ozone as safe alternatives to chemical disinfectants. But the number of cities and the number of people getting water from these methods is minimal.
In the post 9/11 world the contamination of water with biological, chemical or radiological agents has forced the medical community, public health agencies and water utilities to consider the possibility of intentional contamination of US water supplies as part of an organized effort to disrupt and damage important elements of the US national infrastructure. In President Bush's 2002 State of the Union Address, it was noted that confiscated Al Qaeda documents included detailed maps of several US municipal drinking water systems. Some steps have been taken to protect and monitor the US drinking water supply, but currently, it is the healthcare providers that are likely to be the first to observe unusual patterns of illness resulting from the intentional introduction of biological, chemical or radiological agents in the drinking water supply by terrorists. The government has dealt primarily the large scale attacks on the drinking water supply by terrorist, but not adequately with the small scale attacks between the water system operator's plant and the consumer.
In order to minimize liability while increasing the overall health of the public, there is a need to disinfect drinking water inexpensively prior to distribution and a need to purify the disinfectant used by the water system operator and to filter out contaminants, such as, but not limited to, lead from lead pipes, and acts of terrorism before flowing from the consumer's point-of-use, in order to control the quality of water end-to-end in a water filtration and purification distribution system.
Many pipes in the ground are typically on a 50 year depreciation schedule with a 100 year life cycle expectancy, and water system operators face infrastructure replacements issues that are massive, particularly in older cities. The present invention's water system operator's use of water filter/purifiers located near the consumer's point-of-use will dramatically improve the quality of water to the consumer while allowing water system operators to upgrade their distribution systems on a schedule that is manageable. The only way to ensure the quality of water is through the use of “post treatment/post distribution” water filter/purifiers controlled by the water system operator and placed near the consumer's point-of-use. The present invention is a revolutionary concept for a water system operator to adopt and make an integral part of their program.
In April of 2004 the Subcommittee on Water Resources and Environment held a hearing on the state of the United State's aging water supply infrastructure. Concern has been heightened recently over the condition of the nation's water supply infrastructure as a result of the presence of lead pipes in the District of Columbia's drinking water system. The Subcommittee will receive testimony from representatives of the American Water Works Association (AWWA), the Association of Metropolitan Water Agencies (AMWA), the National Rural Water Association, and the U.S. Conference of Mayors' Urban Water Council.
Our nation has over 54,000 community water systems. These systems consist of a substantial amount of infrastructure, including collection devices, drinking water treatment plants, wells, pumps, storage facilities, transmission and distribution water mains, service lines, and other equipment to deliver water. They provide about 90 percent of Americans with their tap water. Approximately 3,000 of these community systems provide more than 75 percent of the nation's water. Our nation's drinking water infrastructure is an asset that all Americans rely on every day. It is a cornerstone of both our nation's economic well-being and our public health. Largely buried underground and invisible to the average American, it is also an asset many have taken for granted.
The greatest challenge facing community water systems today is aging pipes and other water infrastructure. It is not uncommon in older systems to find pipes that were laid in the 19th century. Due to patterns of investment made to serve population growth beginning well over a century ago, water utilities are experiencing an urgent and increasing need to repair and replace this aging infrastructure. As many communities are finding, failure to repair and replace aging infrastructure can result in a loss of valuable water resources, significant economic impacts, and increased risks to public health.
In many cities and towns, water infrastructure has been in place for many decades. Quite often, particularly in the larger cities, components of these systems (such as the water mains) are more than a century old. The oldest cast iron pipes, dating to the latter 1800s, have an average life expectancy of 100-120 years. Because of changing materials and manufacturing techniques, pipes laid in the 1920s have an average life expectancy of nearly 100 years, and those laid in the post-World War II boom are expected to last about 75 years. At this point, these life expectancies are being approached or exceeded in many cities and towns. As the water infrastructure outlives its useful life, it can corrode and deteriorate, resulting in an epidemic of water leakage, burst water mains, unreliable pumps and collection equipment, and aging treatment plants that fail to remove important contaminants. With age and increased demands due to population growth, drinking water infrastructure problems in many cities are growing.
One of the most common problems is water loss from water distribution systems. In most water systems, a large percentage of the water is lost in transit from treatment plants to consumers. The amount of water that is lost is typically 20-30 percent of production. Some systems, especially older ones, may lose as much as 50 percent.
Leakage is usually the major cause of water loss. There are many possible causes of leaks, and often a combination of factors leads to their occurrence. Leakage occurs in various components of the distribution system, including transmission pipes, main distribution pipes, service connection pipes, joints, valves, and fire hydrants. The material, composition, age, and joining methods of the distribution system components can influence leak occurrence. Causes of leaks include corrosion, cracks, material defects or failure due to deterioration over time, faulty installation, inadequate corrosion protection, ground movement over time due to drought or freezing, and repeated excessive loads and vibration from road traffic. Old pipes often leak substantial amounts of water through corroded areas, cracks, and loose joints.
Leaks waste both money and a precious natural resource. The primary economic loss is the cost of the lost raw water, its treatment, and its transportation. Leakage leads to additional economic loss in the form of damage to the pipe network itself. Such damage may include erosion of pipe bedding and pipe breaks, and damage to the foundations of roads and buildings. Leaks also waste substantial amounts of water resources. This is particularly critical in areas where the demand for water is outstripping available supplies. The City of Detroit illustrates the potential cost of water as a lost commodity. In Detroit, citizens endure annual mid-summer water rationing and pressure problems, yet they pay an estimated $23 million per year for water that never reaches their homes and businesses, because over 35 billion gallons of water leak from the Detroit water system each year. The lost water is reflected in bills paid by every household whose water comes from the Detroit system. This is on top of the $1 million the water utility has been spending annually on leak detection and repair, and an ongoing $7 billion capital improvement program.
The problems associated with gradual leakage are compounded when old water mains and other pipes in the water distribution system burst, resulting in the sudden loss of water pressure, flooding, and the loss of even more water. It is common for cities to have scores, hundreds, and even more than a thousand water main breaks each year. For example, last year, there were 1,190 reported breaks along the City of Baltimore's 3,400 miles of water mains, which deliver drinking water to taps across the city and surrounding counties. This is more than three times per day on average. There were 1,140 breaks in 2002. Philadelphia, with a similar amount of pipe, reportedly has an average of 788 ruptures per year, and New York, which has 6,000 miles of mains, has an average of 550 annual breaks. Boston, which has 1,023 miles of pipe, averages 35 breaks per year.
A “reasonable goal” for water systems in North America is 25 to 30 breaks per 100 miles of pipe per year, according to a 1995 American Water Works Association Research Foundation report, Distribution System Performance Evaluation. Baltimore is somewhat above that mark, with an average of 34 breaks per 100 miles over the past two years. Not far behind is the Washington Suburban Sanitary Commission, with 33 breaks per 100 miles. Detroit is worse off, with an average of 45 breaks. Several other cities met the goal, some of them relatively young, affluent communities with moderate weather, but also some of them old, less economically vibrant, and in harsh climates. For every 100 miles of pipe, Phoenix had 29 breaks per year, Pittsburgh had 23, and Hartford 20. Chicago and Providence each had 9. San Diego had 5.
In addition to the substantial direct costs of repairing and replacing burst water pipes, millions of dollars in economic losses are incurred nationally each year as a result of businesses and schools forced to close, flooding and other property damage, closed roads, snarled traffic, and the like. For example, a 36-inch water main which burst in New York City a couple of years ago resulted in severe physical damage because of the ensuing flooding to 14 businesses and business disruptions to an additional 120 businesses, resulting in several hundred thousand dollars in gross revenue loss from the one incident. Small business disaster assistance was made available for the impacted businesses. In Cleveland, a major, 87-year-old water main broke four years ago, flooding downtown streets with some 25 million gallons of water, stranding cars in the flood, closing many businesses and all schools, including Cleveland State University, and leaving 100,000 people without water for a few days. Downtown Cleveland had a second major water-main break about eight months later.
Measures are available to water utilities for reducing water main breaks and other losses of water from their systems. Fundamentally, they involve improved management of a water system's assets. Asset management approaches aim to minimize the total cost of buying, operating, maintaining, replacing, and disposing of capital assets during their life cycles, while achieving service goals. Measures include the systematic collection of key data about the water system; the application of life-cycle cost analysis and risk assessment to set goals and priorities; a systematic program of inspections, monitoring, and leak detection and repair; system maintenance, rehabilitation, and replacement of old pipes and other equipment found to be in need of repair; and corrosion control to reduce the effect of corrosive water on the system.
The General Accounting Office (GAO) issued a report, dated March 2004, in which GAO found that comprehensive asset management has the potential to help utilities better identify needs and plan future investments. Water utilities that GAO reviewed reported that comprehensive asset management provided them with a better understanding of their maintenance, rehabilitation, and replacement needs and thus helped utility managers make better system management and investment decisions. GAO also found that, although smaller utilities face more obstacles to implementing asset management, largely as a result of limited resources, such utilities can also benefit from applying asset management concepts. GAO concluded that EPA can play a stronger role in encouraging water utilities to use asset management by leveraging ongoing efforts within and outside the Agency. Some utilities already are implementing asset management approaches.
The loss of water pressure from water main breaks or other equipment breakdowns also can result in serious contamination of the water supply, thereby creating a public health risk. Additionally, old or poorly maintained pipes may harbor bacteria and other pathogens that can make people sick. Water distribution systems depend on pressure inside the pipes to keep out contamination. If the water pressure drops due to pipe breaks, significant leakage, or pump failures, the possibility increases of bacteria and other contaminants infiltrating into the pipes through leak openings, such as corroded areas, cracks, and loose joints, and contaminating the water. Water utilities typically issue boil-water advisories to customers once water pressure is restored.
Moreover, many older water distribution systems used lead pipes to distribute tap water. Municipalities first installed lead pipes during the late 19th Century. In 1897, about half of all American municipalities used at least some lead water pipes. Lead had two features that made it attractive to the engineers who designed public water systems: it was both malleable and durable. Malleability reduced labor costs by making it easier to bend the service main around existing infrastructure and obstructions, and compared to iron, lead was a soft and pliable metal. As for durability, the life of the typical lead service pipe was considerably longer than plain iron or steel, galvanized, or cement lined pipe. Based solely on engineering concerns, these characteristics made lead an ideal material for service lines. From a narrow engineering stand point, it is clear that lead worked well, when one examines how popular lead service lines were. At the turn of the 20th Century, the use of lead pipes was widespread, particularly in medium and large cities.
However, the use of lead pipes has had public health implications. Studies show that ingested lead can have adverse neurological, toxicological, and developmental effects on humans, particularly children. In cities that used lead water pipes, it appears there were some people who were affected by lead, although the effects of lead water lines varied across cities, and depended on the age of the pipe and the corrosiveness of the associated water supplies. The age of pipe influenced lead content because, over time, oxidation formed a protective coating on the interior of pipes. As for corrosiveness, acidic water leached more lead from the interior of pipes than did non-acidic water.
Over time, the public health implications of lead pipes became better understood, and other materials were used in place of lead pipes. Today, most lead pipes have been replaced with more modern and safer materials, although some cities still have some areas with lead service lines to older buildings and lead-containing packing materials used to seal joints between some pipes. The City of Chicago is reported to have the highest concentration of lead pipes in the nation. Lead service lines remain in some areas in the District of Columbia. The presence of lead materials in water systems is significant because the water passing through lead service lines and joint packing materials could be corrosive, thereby leaching lead from the lines and packing materials and increasing lead levels in the drinking water.
Measures that can be taken by water utilities to reduce lead levels in drinking water include locating and replacing the remaining lead service lines, and reducing the corrosiveness of the water. Many cities that have lead service lines have adjusted their water treatment processes to minimize corrosion. Some, such as Chicago and Philadelphia, add phosphates to the water at their treatment plants. The phosphates, in combination with the natural calcium and magnesium minerals in the water, coat the pipes internally to prevent lead from leaching into the water. The water supplier for the District of Columbia has not adjusted its water treatment to minimize corrosion, and hence, elevated lead levels have been reported in drinking water at some locations. In response to the elevated lead levels that were found, the District's water supplier now is considering adjusting its water treatment processes to add phosphates to the water. It is unclear whether the addition of phosphates to the District's water will ultimately result in any undesirable increases in phosphorus loadings to the Chesapeake Bay from the District's wastewater discharges.
Historically, there had been little Federal assistance for drinking water systems. Local communities and private companies built most of the municipal water systems around the country. Before 1996, the primary source of Federal funding was the U.S. Department of Agriculture (USDA). Through its Rural Utilities Service, USDA has provided both municipal water supply and wastewater treatment assistance of over $600 million a year to communities with populations of less than 10,000.
Following enactment of the 1996 Safe Drinking Water Act Amendments, Congress began providing grants to states to capitalize Drinking Water State Revolving Loan Funds, modeled after the Clean Water State Revolving Loan Funds. Through fiscal year 2004, Congress has provided approximately $7 billion for the Drinking Water State Revolving Loan Funds. Approximately 40 percent of that assistance has been provided for projects to meet treatment needs, and around 30 percent has been for projects to meet transmission and distribution needs. The remaining 30 percent has been provided for water storage, developing sources, technical assistance, and other drinking water needs.
The U.S. Environmental Protection Agency (EPA) submitted a 1999 Drinking Water Needs Survey to Congress in February 2001, pursuant to the Safe Drinking Water Act. The 1999 Needs Survey estimated drinking water infrastructure needs at approximately $150 billion over the next 20 years. Over half of the total drinking water infrastructure needs (56 percent) are for transmission and distribution systems (pipes). Twenty-one percent of the needs are for infrastructure to meet regulatory requirements. The remaining 19 percent of needs are for storage facilities, developing sources, and other needs. EPA acknowledges that its survey likely underestimates needs for transmission and distribution systems because many systems do not have a plan in place for replacing pipes. The Drinking Water Needs Survey is based on documented needs, which only provide an estimate of needs over 5 to 10 years.
In May 2001, the American Water Works Association (AWWA) released a report entitled, “Reinvesting in Drinking Water Infrastructure—Dawn of the Replacement Era.” In that report, AWWA projected that expenditures on the order of $250 billion over 30 years might be needed nationwide for the replacement of worn-out drinking water pipes and associated structures (valves, fittings, etc). This figure does not include wastewater infrastructure or the cost associated with complying with new drinking water standards. A September 2002 EPA report projected that expenditures of $120 billion over the next 20 years might be needed for the replacement of drinking water transmission lines and distribution mains, and another $97.6 billion might be needed for non-pipe (treatment, source, and storage) needs.
There is therefore an unfilled need for a system, method, and apparatus which solves these and other problems. This invention has as its primary objective fulfillment of this need.